The present invention relates in general to remote control of a telephone line, and, more specifically, to use of an intelligent voice response unit to allow a subscriber to implement control actions over their subscribed telephone line connection, such as issuing a busy line interrupt command or other line treatment commands.
Telephone subscribers have customarily not had much control over the behavior or settings of their subscribed telephone line connection. Examples of existing controls include the activation and deactivation of optional features such as call waiting, call forwarding, call park, busy line callback, and automatic number identification (i.e., caller ID). However, other actions such as a busy line interrupt (BLI) have typically continued to require intervention of a telephone operator. Other functions available only to an operator or other telephone company personnel include various treatment codes, such as a re-direct code that causes any call placed from a particular subscriber line to be directed to a predetermined telephone number (e.g., the number of the telephone company billing office when a subscriber's billing account is delinquent). Such treatment codes are implemented within an operational support system (OSS) which comprises a private computer network operated by the telephone carrier which is interfaced to and controls the switches and service control points that handle calls within the public telephone network (making them inaccessible to subscribers).
U.S. Pat. No. 5,905,788, issued to Bauer et al, proposes an automatic system for allowing a subscriber away from home that encounters a busy signal when calling home to interrupt the existing call. During receipt of a busy signal, the subscriber dials an interrupt code that is forwarded to the interexchange carrier (IXC) which verifies the validity of the code and then signals the end office of the local exchange carrier (LEC) to interrupt the call. However, the proposed system in Bauer et al has disadvantages from the standpoint of the LEC because the LEC directly is responsible for the subscriber line performance and it cannot itself verify the authenticity of an interrupt request. Furthermore, in the event that the subscriber line is busy because of a computer dial-up session on the line, then even after the call is interrupted the away-from-home subscriber may still fail to complete a phone call to the line because the computer may immediately re-dial following the interrupt or the computer may auto-answer the operator's call.
U.S. Pat. No. 6,208,718, issued to Rosenthal, discloses measures to handle re-dial attempts by a modem after an operator-initiated line interrupt. A signal recognizable by the modem is transmitted by the telephone network for indicating to the modem that an emergency interrupt took place, so that re-dialing attempts by the modem can be prevented. However, a specially modified modem is required to implement this technique.
Thus, it would be desirable to enable a subscriber (or other authorities) to manage a greater range of behaviors of a subscribed telephone line, whether remotely from another subscriber line or from the subscribed line itself. Further, it would be desirable to ensure the completion of a voice telephone call after interrupting a computer data call on the subscriber line without requiring modifications to a modem.